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In the present density functional theory (DFT) research, nine different molecules, each with different combinations of A (triel) and E (divalent metal) elements, were reacted to effect methane C–H activation. The compounds modeled herein incorporated the triels A = B, Al, or Ga and the divalent metals E = Be, Mg, or Zn. The results show that changes in the divalent metal have a much bigger impact on the thermodynamics and methane activation barriers than changes in the triels. The activating molecules that contained beryllium were most likely to have the potential for activating methane, as their free energies of reaction and free energy barriers were close to reasonable experimental values (i.e., ΔG close to thermoneutral, ΔG‡ ~30 kcal/mol). In contrast, the molecules that contained larger elements such as Zn and Ga had much higher ΔG‡. The addition of various substituents to the A–E complexes did not seem to affect thermodynamics but had some effect on the kinetics when substituted closer to the active site.

Metal borohydride (MBH 4 ) compounds have been studied thoroughly for their potential as hydrogen storage materials. Zirconium borohydrides are one such class of metal borohydrides with hydrogen storage potential, however the interaction between the hydrides from BH 4 − and Zr presents an intriguing feature worth exploring. Cp 2 Zr(BH 4 ) 2 has been investigated for its potential as a hydrogen storage material and as a precursor for other hydrogen storage materials. But, to our knowledge, the structure of Cp 2 Zr(BH 4 ) 2 showing the position of the hydrides is unknown. We present here the crystal structure and DFT calculations of Cp 2 Zr(BH 4 ) 2 showing, for the first time, the position of the hydrides in relation to Zr.

This presentation is part of the Peroxisome Proliferator-Activated Receptors-alpha (PPAR-α) research. PPARs are a group of receptor proteins that function as transcription factors regulating the expression of genes. From our ongoing efforts to study the low molecular mass ligands that binds to these PPARs, we are presenting the reactions of CA with Al 3+ in aqueous solutions. The objectives of this work are: 1-to find whether there is a binding between Al 3+ and CA, and 2-to find what is the binding mode if there is binding. After using the potentiometric technique, the UV-Vis, and IR spectroscopies it appeared that there is strong binding at which a series of ternary Al-CA-OH species are formed. The main complex was [Al(CA)(OH) 3 ] -. These data will be discussed in details.